Control mechanism for automatically timing the fuel injection by an injection pump of an internal combustion engine



April 3, 1956 K. ZIESCHE ETAL 2,740,273

CONTROL MECHANISM FOR AUTOMATICALLY TIMING THE FUEL. INJECTION BY ANINJECTION PUMP OF AN INTERNAL COMBUSTION ENGINE 2 Sheets-Sheet 1 FiledJune 7, 1952 FIG.

April 3, 1956 K. zlEscHE ETAL 2,740,273

CONTROL MECHANISM FOR AUTOMATICALLY TIMING THE FUEL INJECTION BY ANINJECTION PUMP OF AN INTERNAL COMBUSTION ENGINE Filed June 7, 1952 2Sheets-Sheet 2 CONTROL MECHANISM FOR AUTOMATICALLY TIMING THE FUELEJJECTION BY AN INJEC- NINPUMP OF AN INTERNAL CDMBUSTEON Kurt Ziesche,Koln-Holweide, and Josef Berg, Kain-Kath, Germany, assignors toKliickner-Hnmboldt-Deutz Aktiengesellschaft, Koln, Germany ApplicationJune 7, 1952, Serial No. 292,376 Claims priority, application GermanyJune 8, 1951 4 Claims. (Cl. 64-25) This invention relates to controlmeans for internal combustion engines and, more particularly, concerns adevice by which the timing for the fuel injection by the injection pumpis automatically effected in accordance with the speed of rotation bythe variation of the angular position between the driving and the drivenshaft. The change in the angular position between the driving shaft andthe driven shaft is effected by means of a row of members slidablyarranged between guiding elements connected to said shafts. This row ofmembers consists of radially movable centrifugal masses or bodies andintermediate members cooperating therewith in a wedge-like manner.

With a known device of this type, the row of members consists of twoequally spring loaded centrifugal bodies of the same size which areseparated from each other by a wedge-like intermediate member. When achange in the speed of rotation occurs, these two centrifugal bodies,due to their radial movement, bring about an adjustment between thedriving and the driven shaft. The power connection or power flow betweenthese two shafts is maintained by means of a row of elements of equaldimennited States Patent sions which are diametrically opposite said rowof members. These members cooperate in a wedge-like manner so that, whena change in the speed of rotation occurs, the row shortens or lengthensto the same extent as the adjusting angle increases or decreases.However, in an arrangement of this known type, the adjustment is carriedout with relatively great friction losses.

Therefore, it is an object of this invention to provide a controlmechanism which will nearly without friction losses automatically adjustthe point at which the injection pump of an internal combustion enginecarries out its injection step.

It is also an object of this invention to provide a control mechanism ofthe above-mentioned type, which will make it possible, for purposes ofautomatically adjusting the injection point of an injection pump of aninternal combustion engine, to obtain a predetermined ratio between theadjusting angle of the driving and the driven shaft.

It is still another object of this invention to provide a controlmechanism as set forth in the preceding paragraph in which the adjustingangle between the driving and the driven shaft will change linearly ornearly linearly in conformity with a change in the speed of rotation ofsaid shaft.

These and other objects and advantages will appear more clearly from thefollowing specification in connection with the accompanying drawingshowing in Fig. l

the control mechanism proper, while Fig. 2 shows the operativeconnection between the said control mechanism and the injection pump tobe controlled.

General arrangement With the device according to the present inventionthe driving and the driven shafts rest against each other through anelastic or yielding member. Furthermore, the centrifugal bodies arespring loaded. The elastic support of the two shafts against each otherin connection with a row of members consisting of spring loadedcentrifugal bodies has the great advantage that, due to the advancing ofthe injection pump shaft following the injection, the sliding surface ofthis shaft can space itself from the row of members so that thecentrifugal bodies become free and can move nearly by themselves inconformity with the centrifugal force acting thereupon. Nevertheless,particularly in view of the thrust of the springs acting upon thecentrifugal bodies, there will always result a stable equilibrium forthe said centrifugal bodies. This is true for a self-blocking as well asfor a non-self-blocking row of members. If no self-blocking arrangementis provided, care has to be taken by correspondingly balancing thecentrifugal masses so that, within the short pressure period during theinjection, the centrifugal bodies due to their inertia will not carryout any material dodging movement. With devices in which the driving andthe driven shaft restagainst each other through rigid members adapted tododge during the adjustment, a freeing of the centrifugal bodies is notpossible. With a known device for the automatic control of thepre-ignition in connection with internal combustion engines, the drivingshaft rests against the driven shaft through two springs; however, thecentrifugal bodies of the row of members consist of free flying balls.

According to a further development of the invention, the centrifugalbodies may be dimensioned as to weight or shape, and also the springsacting thereupon may be so dimensioned that, when a change in the speedof rota-' tion occurs and as a result thereof the centrifugal bodiesmove, the latter will differently vary the total adjusting stroke of therow of members. In this way, a predetermined ratio can be obtainedbetween the adjusting angle and the change in the speed of rotation. Itis preferable to dimension the centrifugal bodies and the springs actingthereupon in such a manner that the adjusting angle will vary linearlyor nearly linearly in conformity with a change in the speed of rotation.According to a particularly simple manner, the centrifugal bodies may beidentical as to shape and weight, whereas the springs acting thereuponmay be differently dimensioned so that, with increasing speed ofrotation, one centrifugal body after the other will become effective.

Structural arrangement Referring now to the drawing in detail, thestructure shown therein comprises an outer annular or ring member 1which is connected with the driving shaft 2 shown in Fig. 2. A drivenshaft 2 extends concentrically into ring 1. Shaft 2' is provided with anoutwardly extending extension member 3 and rests against ring 1 throughsaid extension member 3 and a spring 4 and through a radially inwardlyextending extension member 5 of ring 1. Those sides of the extensionmembers 3 and S which are remote from the spring 4 slope toward theshaft 2' and spring 4. Between the two sloping surfaces 6 and 7 of theextension members 3 and 5 there is provided a row of members whichconsist of radially movable centrifugal bodies 8, 9, 10 and 11 andintermediate members 12, 13 and 14 cooperating in a wedge-like mannerwith said centrifugal bodies 8, 9, 10 and 11. The centrifugal bodies areacted upon by radially inwardly acting springs 15, 16, 17 and 18. Thecentrifugal bodies and the intermediate members cooperate in awedge-like manner in such a way that, when the centrifugal bodies moveoutwardly, the total longitudinal extension of the row of membersincreases. In order to enable the row of members when it lengthens toadapt itself to the changing angle between the sloping surfaces 6 and 7,the intermediate members 12 and 14 are provided along their slopingsurfaces with sliding shoes 19 which are provided with a semi-circularsurface by means of which they are resting in said intermediate membersin a self-aligning manner. The intermediate members 12, 13 and 14 areinserted in ring 1 in such a manner that they can slide along the innerperipheral area of ring 1. The centrifugal bodies are equallydimensioned as to shape and weight.

The operation of the device is as follows: it may be assumed that thedevice is at a standstill and that now the speed of rotation begins toincrease to such an extent that the centrifugal bodies 8 to 11 moveoutwardly. As a result thereof, the total length of the row of memberslengthens and the relative rotational angle adjustment between thedriving and the driven shaft changes against the thrust of the spring 4.Inasmuch as with identical centrifugal bodies and identical loadingsprings, the angle adjustment in conformity with the speed of rotationwould change parabolically in an undesired manner, the springs aredifierently dimensioned. More specifically, the springs are sodimensioned that the course or graph indicating the ratio between thechange in the angle and the speed of rotation is represented by fournearly linearly extending successive parabolic sections. Inasmuch as thetwo shafts elastically rest against each other through spring 4, thesloping surface 6 spaces itself from the row of mem bers when after theinjection the driven shaft 2' runs ahead. As a result thereof, thecentrifugal bodies move nearly frictionless into their respectiveposition corresponding to the respective centrifugal force.

It is preferable to make the intermediate members 12 and 14 of porousmaterial, for instance, sinter material. This has the advantage thatthese parts fill themselves with oil and thus assure a sufficientlubrication of the sliding shoes 19 which oscillate only slightly.

It is, of course, understood that the present invention is, by no means,limited to the particular construction shown in the drawing but alsocomprises any modifications within the scope of the appended claims.

What we claim is:

l. A device for automatically adjusting the timing for the injection offuel by the injection pump of an internal combustion engine, whichcomprises in combination: a driving shaft provided with annular meanshaving radially inwardly extending extension means, a driven shafthaving radially outwardly extending extension means within said annularmeans and near said first-mentioned extension means, saidfirst-mentioned extension means and said second-mentioned extensionmeans being respectively provided with a sloping guiding surface atthose ends of said first-mentioned and second-mentioned extension meanswhich are remote from each other, a row of radially movable centrifugalmembers arranged between said guiding surfaces and provided withoutwardly tapering surfaces, said sloping guiding surfaces respectivelybeing parallel to the adjacent tapering surfaces of the respectiveadjacent centrifugal members, intermediate members respectivelyinterposed between each two adjacent centrifugal members for cooperationwith the adjacent tapering surfaces thereof, a first coil springinterposed between adjacent ends of said first-mentioned andsecond-mentioned extension means and representing an elastic drivingpower conveying means between said two shafts, and a plurality of secondcoil springs arranged substantially co-axially with and extending inradial direction of said centrifugal members and continuously urgingsaid centrifugal members toward said driven shaft but adapted to allowsaid centrifugal members to move against the thrust of said secondsprings in response to a predetermined centrifugal force.

2. A device for automatically adjusting the timing for the injection offuel by the injection pump of an internal combustion engine, whichcomprises in combination: a driving shaft provided with annular meanshaving first extension means extending inwardly from said annular means,a driven shaft having second extension means within said annular meansand near said first extension means, said first extension means and saidsecond exten' sion means being respectively provided with a slopingguiding surface at those ends of said first and second extension meanswhich are remote from each other, a row of radially movable centrifugalmembers arranged between said guiding surfaces and provided withoutwardly tapering surfaces, said sloping guiding surfaces respectivelybeing parallel to the adjacent tapering surfaces of the respectiveadjacent centrifugal members, intermediate members provided withlubricant-storing pores and respectively interposed between each twoadjacent centrifugal members for cooperation with the adjacent taperingsurfaces thereof, a first spring interposed between adjacent ends ofsaid first and second extension means and representing an elasticdriving power conveying means between said driving shaft and said drivenshaft, and second springs spaced from said adjacent ends of said firstand second extension means and arranged continuously to act upon saidcentrifugal members in the direction of the radial movement thereof andcontinuously to urge said centrifugal members toward said driven shaft,said second springs being arranged to allow said centrifugal members tomove against the thrust of said second springs in response to apredetermined centrifugal force acting upon said centrifugal members.

3. A device for automatically adjusting the timing for the injection offuel by the injection pump of an internal combustion engine, whichcomprises in combination: a driving shaft provided with annular meanshaving first extension means extending inwardly from said annular means,a driven shaft having second extension means within said annular means,said first extensionmeans and said second extension means beingrespectively provided with a sloping guiding surface at those ends ofsaid first and second extension means which are remote from each other,first spring means interposed between the two adjacent ends of saidfirst and second extension means to allow said shafts to turn relativeto each other by a limited angle, a row of radially movable centrifugalmembers arranged between said guiding surfaces and provided withoutwardly tapering surfaces, said sloping guiding surfaces respectivelybeing parallel to the adjacent tapering surfaces of the respectiveadjacent centrifugal members, intermediate members respectivelyinterposed between each two adjacent centrifugal members for cooperationwith the adjacent tapering surfaces thereof, and a plurality of secondspring means independent of said first spring means and spaced from saidtwo adjacent ends of said extension means, said second spring meanscontinuously acting upon and urging said centrifugal members in radialdirection toward said driven shaft and being arranged to allow saidcentrifugal members to move radially outwardly against the thrust ofsaid spring means in response to a predetermined centrifugal forceacting upon said centrifugal members.

4. A device for automatically adjusting the timing for the injection offuel by the injection pump of an internal combustion engine, whichcomprises in combination: a driving shaft provided with annular meanshaving radially inwardly extending extension means, a driven shafthaving radially outwardly extending extension means within said annularmeans and near said first mentioned extension means, said firstmentioned extension means and said second mentioned extension meansbeing respectively provided with a sloping guiding surface at those endsof said first mentioned and second mentioned extension means which areremote from each other, a row of radially movable centrifugal membersarranged between said guiding surfaces and provided with outwardlytapering surfaces, said sloping guiding surfaces respectively beingparallel to the adjacent taperingsurfaces of the respective adjacentcentrifugal members, intermediate members respectively interposedbetween each two adjacent centrifugal members for cooperation with theadjacent tapering surfaces thereof, a first spring interposed betweenadjacent ends of said first mentioned and said second mentionedextension means and representing an elastic driving power conveyingmeans between said two extension means, and a plurality of secondsprings spaced from said adjacent ends of said first mentioned andsecond mentioned extension means and continuously urging saidcentrifugal members toward said driven shaft but adapted to allow saidcentrifugal members to move radially outwardly against the thrust ofsaid second springs in response to References Cited in the file of thispatent UNITED STATES PATENTS Fuchs July 31, 1917 Lang Apr. 30, 1935

